m68k: use non-MMU linker script for ColdFire MMU builds

Use the non-MMU linker script for ColdFire builds when we are building
for MMU enabled. The image layout is correct for loading on existing
ColdFire dev boards. The only addition required to the current non-MMU
linker script is to add support for the fixup section.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Matt Waddel <mwaddel@yahoo.com>
Acked-by: Kurt Mahan <kmahan@xmission.com>